jahangir khajehali

The fumigant, repellent, contact toxicity, and phytotoxicity of essential oils from Mentha pulegium, M. piperita, Cuminum cyminum, and Myrtus communis were investigated against the cotton aphid, Aphis gossypii (Glover). GC- MS analyzed the composition of essential oil. The primary constituents of the essential oils from M. pulegium, C. cyminum, M. piperita, and M. communis were pulegone (63.88%), cuminic aldehyde (28.20%), menthol (36.94%), and 1, 8-Cineole (36.13%), respectively. The LC50 toxicity values showed that the essential oil from M. pulegium was the most toxic against A. gossypii. In the contact toxicity bioassay, the essential oil of C. cyminum was more harmful than the others. All formulations, except for M. piperita had a repellent effect on adult aphids. When used at the highest tested doses, all formulations of essential oils caused phytotoxicity to the cucumber leaves. Based on our results, the essential oils of M. pulegium, C. cyminum, M. piperita, and M. communis plants could be developed into effective fumigants.

The greenhouse whitefly, Trialeurodes vaporariorum (Westwood), is one of the harmful pests of vegetables and ornamental plants. The high damage caused by this pest has made it necessary to design an integrated pest management (IPM) programs based on biology and its symbiotic relationships. Since the symbionts of greenhouse whiteflies are less known so far in Iran, their diversity in different pest populations has been investigated in the upcoming research. For this purpose, sampling was done from contaminated greenhouses and fields of Isfahan province. Then, DNA extraction and polymerase chain reaction (PCR) were performed to assess the presence/absence of symbionts, sequencing of target genes, and molecular identification of the whitefly species. Also, the cotton whitefly, Bemisia tabaci (Gennadius), was used as a control in different stages. The target species was identified as T. vaporariorum based on the morphology and cytochrome oxidase one (COI) gene sequence. Examining the diversity of symbionts showed the presence of Portiera sp. and Arsenophonus sp. in all collected populations. Hamiltonella sp. and Rickettsia sp. were detected in all populations except Kholenjan and Bagh Abrisham. Cardinium sp. has been observed in the population of Yafran and Fritschea sp. was detected in the populations of Khomeini Shahr, Nasim Abad, Kholenjan, Bagh Abrisham, and Yafran, while Wolbachia was not detected in any of the populations. Considering the lack of information about the symbiotic diversity of the greenhouse whitefly and also the lack of studies in Iran, this research can be a basis for further studies in the field of symbiosis and to recognize the role of symbionts.

Root and crown rot disease of apple trees is important in different regions of the world and causes considerable damage to apple orchards around the world annually. Due to the presence of newly known fungal agents in apple growing areas of Isfahan province, sensitivity of Fusarium solani and F. oxysporum species as the most abundant identified species of decay of apple trees compared to common fungicides including Tilt, Eminent, Cabrio Duo, Collis, Ortiva Top, Lamardor, Uniform, Flint, Stroby, Rovral TS and Topsin M at concentrations of 10, 25, 50, 100 and 200 mg/l were tested in vitro. Lamardor, Rovral TS, Ortiva top and Tilt fungicides at the highest tested concentrations in both Fusarium species and Eminent at all tested concentrations in F. oxysporum resulted in more than 50% mycelial growth inhibition in vitro, in comparison with the other fungicides. Although, performing a laboratory test is very useful in the initial screening of fungicides, but in order to definitively recommend a fungicide to control the disease, in addition to fungicides experiment in vitro, testing in greenhouse and field conditions is also necessary.

Insecticide resistance is one of the most important problems associated with the control of Musca domes tica, due to the potential of the rapid development of resistance to different chemical insecticides. The present study was carried out to evaluate dichlorvos resistance in the house fly populations collected from central regions of Iran, Isfahan Province and Chaharmahal and Bakhtiari Province, during 2017 to 2019.

Bioassays were carried out using a standard topical application method as well as a fumigation method. The Koohrang population (susceptible) with the lowest LD50 values to dichlorvos was chosen to calculate the resistance rati os (RR). Altered sensitivity of acetylcholinesterase (AChE), a target enzyme for dichlorvos, was investigated.

According to the results, very high levels of dichlorvos resistance were observed in the Mobarake population (RR= 80.25-fold by topical application and 33-fold by fumigation bioassay), and Isfahan population (RR= 107.30-fold by topical application and 43-fold by fumigation bioassay) compared to the Koohrang population. Acetylcholinesterase of the Koohrang population was the most sensitive to inhibition by dichlorvos based on the determination of median inhibitory concentration (IC50), but AChE of Mobarake and Isfahan populations were 741.93- and 343.94- fold less sen sitive to inhibition.

The insensitivity of AChE was possibly involved in dichlorvos resistance in the house fly populations.

Mites are among the most important members of soil arthropod communities, because they are the most diverse in terms of ecological niche and behavior. Due to the sensitivity of soil mites to soil disturbance, their diversity and numbers can be used as ecological indices for assessing disturbances in ecosystems. To determine the effect of land use type on soil mite biodiversity, abundance and biodiversity indices of soil inhabiting mesostigmatic mites were evaluated at eight sites in Saman and Shahrekord, Iran, each site including two adjacent agricultural pieces of land: an orchard and a crop field. The biodiversity of mites was measured by several biodiversity indices and then compared by analysis of variance. The specimens collected belonged to 12 families, 17 genera and 24 species. The biodiversity index values calculated in different months showed that these indices were usually higher in warm months and in orchards than in cold months and crop fields. In the examined crop fields, the diversity index values were lower after harvesting, probably due to soil disturbance by agricultural machinery. There was a significant difference in the Shannon-Wiener's diversity index among different land uses. The maximum and minimum values of this index were recorded at the vine orchard (1.48) and wheat field (0.15) in an elm/wheat site at Shahrekord, respectively. The soil organic matter content was maximum in the vineyard (2.12%) and minimum in the wheat field (0.41%).

Potato tuber moth (PTM), Phthorimaea operculella (Lep.: Gelechiidae) is a serious pest of potato, Solanum tuberosum (Solanaceae). To study factors influencing capture of male PTM by pheromone traps, two sets of experiments were conducted in a split-plot factorial design. In the first experiment, four factors were studied: potato cultivar (Agria, Marfona, Jelly, Arinda, Santea and Sabalan), storage type (cold and conventional), trap shape (funnel and delta) and trap color (white and green). Significant differences were found among storage types and potato cultivars. Total moth catches were eight times higher in conventional storage than that of cold storage. Agria and Marfona cultivars had the highest capture, while Arinda and Sabalan cultivars had the lowest. There were no significant differences between trap shapes and trap colors. Results showed that trap catches in different cultivars were affected by storage conditions. In cold storages the highest and lowest captures were 7.00 and 5.58 moth/trap/week, whereas in conventional storages the highest and lowest captures were 59.9 and 42.3. The second experiment was aimed to assess the effect of cellulose mulch on the capturing of PTM in conventional storages containing Agria. Results showed that pheromone traps in control (no-mulch) treatments caught three times more PTM than the mulched treatments. It is concluded that lower numbers of PTM were caught in potatoes held in cold storages than that of conventional storages. Otherwise, in conventional storages, cellulose mulch can be applied to reduce PTM population density.

The grape leafhopper, Arboridia kermanshah Dlabola (Hemiptera, Cicadellidae), is one of the most economically important pests of most vineyards in Isfahan. Seasonal changes of the pest were determined on nine cultivars including White Yaghotii, Black Yaghotii, Askari, Rishbaba, Khalili, Rotabi, Red Keshmeshi, Black and White Keshmeshi in a randomized complete blocks design with split plots. In the present study, the highest density of adults and nymphs were observed in late May and June. Also, in the first decade of July, due to increased adult density, the egg density reached its highest level. The increase parasitism and cold weather in the late season leads to a reduction in the density of nymphs and adults, and ultimately the pest injury reached its lowest level at the end of the season. The results showed that the seasonal changes of the adults, nymphs and percentage of leaf injury had significant differences between grape cultivars. The highest population density of adults, nymphs and percentage of damage were observed on White Yaghotii. The lowest number of adults and damage percentage were recorded on Black Yaghotii, Red Keshmeshi, and White Keshmeshi. Considering differences in the population and injury of the pest on different grape cultivars, selection of suitable grape varieties can be helpful in the integrated pest management of A. Kermanshah.

The grape leafhopper, Arboridia kermanshah Dlabola (Hemiptera, Cicadellidae), is an economically important pest in most vineyards of Isfahan. In this study oviposition preference and nymphal developmental time of the pest were studiedon nine cultivars including White Yaghotii, Black Yaghotii, Askari, Rishbaba, Khalili, Rotabi, Red Keshmeshi, Black and White Keshmeshi under field and semi-field conditions in Isfahan University of Technology vineyard in two consecutive years. No-choice oviposition preference test was performed using leaf cages under natural conditions and results showed that the highest number of eggs laid per female was obtained on Rish-baba and the lowest amount was recorded on Black Yaghotii cultivar. Based on the choice oviposition preference test, using pots in the semi-field conditions, the highest and lowest oviposition rate were recorded on White Yaghotii and Black Yaghotii, respectively. In addition, the developmental times of different nymphal instars of the grape leafhopper were determined on several grape cultivars in natural conditions. The maximum duration of the total nymphal period (29.33±0.3 days) was observed on the Black Yaghotii and the lowest (26.33±0.88 days) on the White Yaghotii. Results of the oviposition preference and duration of the nymphal period indicated that White Yaghotii and Black Yaghotii were the most and least suitable hosts for A. Kermanshah, between the tested cultivars. In this study, no significant correlation (r2=0.18, P>0.05) was found between oviposition preference of A. kermanshah, respectively, and the leaf hair density of different grape cultivars.

Soil microorganisms are the essential part of forest ecosystems which play a key role on soil nutrient changes. The biological activity in soil is largely concentrated in topsoil. Despite the small volume of microorganisms in soil, they have a key role on nitrogen, sulphur and phosphorous cycles and the decomposition of organic residues. Soil microorganisms have been identified as the sensitive indicators for soil quality. The composition of microorganisms and their fractional activities in soils significantly affect biochemical cycles, carbon sequestration and soil fertility. As soil microbial communities respond differently respected to environmental conditions, it seems that variation in forest ecosystem could significantly affect microbial community. Plants are one of the important variables for assessing soil microbial communities which their effect is related to root secretions and litter decomposition. The phospholipid fatty acid (PLFA) analysis is one of the methods that can overcome the problem of selective growth of microorganisms on culture media which is a major defect in the identification of microbial diversity. The objective of this study was to investigate the effects of different tree compositions and soil properties on soil microbial community using PLFA analysis approach.
This study was conducted in ShastKalate forest, an experimental forest station of Gorgan University, located at eastern Caspian region, North of Iran (36° 43′ 27″ N ,54°24′ 57″ E). Eleven different tree compositions were selected and the surface soils collected from 0-10 cm depth of 33 plots. Soil samples were air dried and passed through a 2mm sieve. Then one portion of the sieved samples was used for physical and chemical analyses. The other portion was rewetted to 65% of field capacity and incubated at 37 °C for 3 days to analyses PLFA. Soil particle size distribution (clay, silt and sand) was determined using the hydrometer method. Soil pH in 1/ 2.5 soil to water suspension and electrical conductivity (EC) in the same extract were measured.. Calcium carbonate equivalent (CCE),soil organic carbon (OC) and total nitrogen (TN) was determined, too. Biological analyzes including soil microbial respiration determination and PLFA analysis were carried out. The PLFA detection and quantification were performed with a Hewlett-Packard 5890 Series II gas chromatograph (GC) equipped with an HP Ultra 2 capillary column and a flame ionization detector. The normalized data were employed for Pearson's correlation analysis and ANOVA to determine the effects of soil properties and different tree compositions on soil microbial community.
Gram and Gram- bacteria were the most microorganisms and protozoa were the least microorganisms in soil samples. The results of the correlation between soil properties and microorganisms showed that OC and TN had significant positive effects on microorganism’s communities. EC was significantly correlated with Arbuscular Mycorrhizal Fungi (AMF), actionbacterial, protozoa and total PLFA. In addition, soil microorganisms and total PLFA were significantly correlated with soil respiration. However, there was no significant correlation between TN and OC with protozoa. The correlations between pH, EC, CCE and sand with protozoa were significantly negative, but in the case of silt, this correlation was significantly positive. Different studies showed that soil organic matter is the main nutrient source for soil microorganisms and soil microorganisms are also the essential part of C and N cycles. The effects of tree compositions on 16:0 10-methyl, 18:2 w6c, 20:2 w6c, 20:3 w6c and 20:4 w6c were significant(p

To determine armyworm species in sugar beet fields in Isfahan, monthly or biweekly sampling of lepidopteran larvae or pupae from soil or beet leaves was conducted in Abrisham town of Isfahan, Iran in 2014. Samples were sent to the laboratory and their DNA was extracted after reaching adult stage and morphological identification was performed. Afterward, a region of the Cytochrome Oxidase I gene was PCR amplified using Lep – F / R primers and was sent to Macrogen Inc. company (Seoul, Korea) for sequencing. The amplified segment alignment and its BlAST with the sequences available in NCBI showed that among the identified samples, only one sample had 100% similarity with Anarta trifolii (hufnagel, 1766) sample from Canada. Species composition of noctuids was determined by collecting 476 larvae or pupae in 10 sampling times. Spodoptera exigua (42.65%) and A. trifolii (38.45%) had the highest frequency of noctuid species.

The beet armyworm, Spodoptera exigua, is one of the most important pests of sugar beet in Iran. The aim of this study was to determine the effect of water and nitrogen treatments of sugar beet planton developmental time and fecundity life table parameters of the pest. An experiment was carried out under laboratory conditions (25±2oC, 70±5% R.H. and 12L: 12D) on larvae reared on sugar beet leaves collected from different treated plants. Treatments consisted of three irrigation regimes, irrigation after 70, 105, 140 mm of cumulative evaporation from class A pan, and also three N-fertilizer levels, 200, 150, 100 kg/ha net nitrogen. The results showed that the longest larval and pupal developmental time, the lowest pupal weight and the shortest adult longevity were observed in 70 mm cumulative evaporation treatment. Additionally, the longest pupal developmental time, the lowest pupal weight and the shortest adult longevity were in 100 kg/ha net nitrogen treatment. Larvae reared on leaves collected from 105 mm cumulative evaporation and 200 kg/ha net nitrogen treatment resulted in the highest intrinsic rate of increase (rm), net reproductive rate (Ro), gross reproductive rate (G. R. R.), finite rate of increase (λ), the shortest mean generation time (T) and doubling time (t). This indicated that moderate drought stress and the highest amount of nitrogen fertilizer may increase the population density of the pest

Soil-dwelling mites and especially Gamasina (Mesostigmata) are very important to soil ecosystems. They are one of the major groups rich in species and abundance. In order to study mesostigmatic mite fauna, soil samples were collected from different oak forests of Lordegan region. The mites were extracted using Berlese-Tullgren funnels and then cleared in Lactic acid and mounted in Hoyer''s medium. This study reports on the distribution of soil mesostigmatids in Iran and world-wide. Twenty species belonging to 13 genera of five families were collected and identified. Species are listed as follows: Ascidae: Arctoseius cetratus (Sellnick, 1940), Gamasellodes bicolor (Berlese, 1918), Antennoseius (Antennoseius) bacatus Athias-Henriot, 1961, Antennoseius (Antennoseius) masoviae (Sellnick, 1943). Blattisociidae: Lasioseius youcefi Athias-Henriot, 1959. Laelapidae: Cosmolaelaps rectangularis Sheals, 1962, Euandrolaelaps karawaiewi (Berlese, 1903), Gaeolaelaps aculeifer (Canestrini, 1883), Gaeolaelaps minor (Costa, 1968), Gaeolaelaps oreithyiae (Walter & Oliver, 1989), Haemolaelaps fenilis (Megnin, 1875), Haemolaelaps shealsi (Costa, 1968), Haemolaelaps schusteri (Hirschmann, 1966), Laelaspis kamalii Joharchi and Halliday, 2012, Laelaspis missouriensis (Ewing, 1904), Gymnolaelaps canestrinii (Berlese, 1903), Gymnolaelaps obscuroides (Costa, 1968). Ologamasidae: Sessiluncus hungaricus Karg, 1964, Allogamasellus sp.; Veigaiidae: Veigaia planicola Berlese, 1882. The genus Allogamasellus and Haemolaelaps schusteri are reported for the first time for Iranian mite fauna and the male of Laelaspis kamalii is reported for the first time for world fauna.

Pollinators and seed predators may strongly influence some of the plant reproductive fitness measures. For supporting conservation and development of the plant species with local dispersal، identification of favorable and unfavorable factors on the species reproduction is needed، especially in the case of palatable and nitrogen-fixing legumes with high nutritional value. This study aimed atdetermining the role of pollinators and seed predators and their interaction in seed production of Hedysarum criniferum Boiss. To achieve the goal، the following treatments were applied in the natural habitat of the plant: pollinators excluded/seed predators present; seed predators excluded/pollinators present; seed predators excluded/pollinators excluded; and a control (neither excluded). Tulle-mesh cages were used to prevent insect pollinators and seed predators to affect the plants. The response variables were the number of seeds produced per plant، the number of loments produced per plant and the proportion of attacked fruits by seed predators per plant. The results showed that the pollination impact was supportive and caused a 47. 6 fold increment in loments and a 62. 6 fold increase in produced seeds compared to their absence. It was found that the pollinators were more effective than the seed predators on the reproduction of this plant. In addition، the seed predators infected 27% of the seeds compared to the control. Despite the fact that seed predators caused the loss of about one-fourth of the seeds، the healthy seeds produced by the plant was sufficient such that seed predators were not a significant threat to the plant’s survival. Consequently، seed predators possibly could not be considered as the main factor for patchiness in the distribution of H. criniferum. Moreover، a non-significant herbivory × pollination interaction on seed production of H. criniferum (p≥0. 05) was found.

Laboratory and field experiments were conducted to determine the efficacy of some insecticides on the control of Sarta longhorned beetle, Aeolesthes sarta Solsky adults and larvae. In the laboratory, three pairs of mated and non-oviposited adults were released on the logs of field elm, Ulmus minor Mill that had been treated with chlorpyrifos, carbaryl, permethrin or imidacloprid. In the field experiments, artificially infested U. minor var. umbraculifera Rehd trees were treated by imidacloprid and oxydemeton-methyl through soil and trunk injection. In the laboratory test the best results were obtained from imidacloprid and permethrin applications, because of occurrence of high adult mortality after short period and also preventing egg laying. Despite a few eggs that were laid on the chlorpyrifos treated logs, there were no living larvae in the sprayed logs. Results of the field tests showed that the number of living larvae did not differ significantly between oxydemeton-methyl and control treatment, however, imidacloprid injection was effective in controlling this pest.

Elm aphids damage elm trees through feeding and producing considerable amounts of honeydew especially on trees of recreational areas. Biological characteristics and seasonal fluctuations of the aphid were studied in two sites by weekly sampling from infested trees during 2002-2003. To determine important life table parameters of the aphid، Tinocallis nevskyi Remaudiere، Quednau and Heie، in natural conditions leaf cages were used. The results indicated that the aphid overwinter as egg on the branches of trees. First nymphs and alatae were observed in early and late April، respectively. The population of viviparae was increased rapidly in late April and May and went down in summer. Wingless oviparae and alate males appeared in mid fall. Oviposition occurred in early November to early December. Intrinsic rate of increase (rm)، Finite Capacity for Increase (ʎ)، net reproductive rate (R0) and mean generation time of the aphid were 0. 15±0. 02 day-1، 1. 17±0. 04 day-1، 14. 89 ±1. 54 nymphs and 17. 54±0. 30 days، respectively.

In order to determine the level of residual Dichlorvos pesticide on strawberry fruits in research greenhouse conditions in crop year of 2011-2012, a study was carried out in Education and Research Center for Greenhouse Productions of Islamic Azad University of Khorasgan of Isfahan. Factorial experiment was carried out based on a completely randomized design with two factors of pesticide consumption and different harvesting hours after spraying with 2 and 5 levels with 3 replications. In order to determine the amount of pesticide residues, GC-ECD device was used. The results showed that between the two pesticide usage levels (twice the recommended dose and the recommended dose), there was no statistically significant difference at the 5% level. However, among the hours after harvest, some differences were observed between the two doses, so between 1 hour after spraying and 7 days after spraying, the residual amount was different. At the end it was found that at the recommended dose and double recommended dose treatments in 7 days after spraying with pesticide, the amount of residues of Dichlorvos reached to allow limit of this pesticide residue (0.10) for export to the Europe Union countries.

The beet armyworm, Spodoptera exigua, is one of the most important pests of sugar beet in Iran. The aim of this study was to determine the effect of water and nitrogen treatments of sugar beet planton developmental time and fecundity life table parameters of the pest. An experiment was carried out under laboratory conditions (25±2oC, 70±5% R.H. and 12L: 12D) on larvae reared on sugar beet leaves collected from different treated plants. Treatments consisted of three irrigation regimes, irrigation after 70, 105, 140 mm of cumulative evaporation from class A pan, and also three N-fertilizer levels, 200, 150, 100 kg/ha net nitrogen. The results showed that the longest larval and pupal developmental time, the lowest pupal weight and the shortest adult longevity were observed in 70 mm cumulative evaporation treatment. Additionally, the longest pupal developmental time, the lowest pupal weight and the shortest adult longevity were in 100 kg/ha net nitrogen treatment. Larvae reared on leaves collected from 105 mm cumulative evaporation and 200 kg/ha net nitrogen treatment resulted in the highest intrinsic rate of increase (rm), net reproductive rate (Ro), gross reproductive rate (G. R. R.), finite rate of increase (λ), the shortest mean generation time (T) and doubling time (t). This indicated that moderate drought stress and the highest amount of nitrogen fertilizer may increase the population density of the pest